Soil sampling equipment



July 3, 1962 A. G. ANDERSSON 3,042,124

son. SAMPLING EQUIPMENT Filed Oct. 27, 1959 2 Sheets-Sheet 1 l/V VE NTOR ANDERS G- L. ANDERSSON BY W a 6.

HTTORNEYS y 1962 A. G. L. ANDERSSON 3,042,124

SOIL SAMPLING EQUIPMENT Filed Oct. 27, 1959 2 Sheets-Sheet 2 ANDERS G.L. ANDERSSON 3,042,124 Patented July 3, 1962 3,042,124 SOIL SAMPLINGEQUIPMENT Anders G. L. Audersson, 1415 Queens Ave., West Vancouver,British Columbia, Canada Filed Oct. 27, 1959, Ser. No. 848,992 6 Claims.(Cl. 175-20) This invention relates to soil sampling equipment.

In investigations of the distribution, type and physical properties ofthe soil below ground surface level, it is often desirable to be able toextract continuous, preferably undisturbed, samples of soil. Thesampling method of subsurface exploration provides practicallycontinuous and representative samples of the sub-soil and is probablythe best method yet devised for obtaining detailed and reliableinformation on the characteristics of the sub-soil. The most common andeflicacious type of sampler is the drive sampler which consistsessentially of a tube which is advanced into the soil in the axialdirection. There are various types of drive samplers in general use andthese may be broadly classified in two groups, namely, open samplers andpiston samplers. In the case of open samplers, the tube is always openat its lower end; the soil enters the tube as soon as it is forced intothe ground. With piston samplers, on the other hand, the lower end ofthe tube is temporarily sealed as by a piston or a plug so that soil canbe prevented from entering the sampler until it has been driven into thesoil to the desired sampling depth, whereat the piston is released orretracted where-after further advance of the sampler into the soilforces a sample into the lower end of the tube.

The present invention is particularly concerned with soil samplingequipment of the retractable-piston type and it is a primary object ofthis invention to provide sampling equipment of this type which can beoperated by means of a single line of extensions thereby materiallyreducing the advancing and withdrawal time.

It is a further object of the invention to provide a sampler of thistype which can be subjected to practically unlimited driving force if sorequired in order to advance it into the sub-soil, thereby rendering itsuitable for use in practically all types of soil.

It is another object of the invention to provide a sampler of theretracted-piston type in which prior to its withdrawal a partial vacuumis created above the sample to assist in retaining the sample duringwithdrawal.

It is a still further object of the invention to provide a sampler whichis of simple, yet robust, construction and which has no delicate partsliable to malfunction under exacting field conditions.

Other features which may be included in accordance with the inventionwill hereinafter be described and referred to in the appended claims.

The invention will be more fully understood from the followingdescription taken in conjunction with the annexed drawings which show byway of example one embodiment of the invention and in which:

FIGURES 1 and 2 are longitudinal sectional views through the lower andupper ends respectively of the sampler with the piston at itsfully-advanced position.

FIGURES 3 to 7 inclusive are cross-sectional views on the lines 33, 44,5-5, 6-6 and 77 respectively of FIGURES l and 2,

FIGURE 8 is a longitudinal sectional view through the lower end of thesampler with the piston in its partially retracted or sampling position,

FIGURE 9 is a longitudinal sectional view through through the lower endof the sampler with the piston at its fully retracted withdrawalposition,

FIGURE 10 is a fragmentary perspective view show ing a detail of themeans for interlocking the rod and the casing,

FIGURE 11 is a cross-sectional view on the line 11- 11 of FIGURE 8, and

FIGURE 12 is a cross-sectional view on the line 12-- 12 of FIGURE 9.

The sampler consists essentially of a casing indicated generally at 12,a piston 14, and a rod 16 connected to the upper end of piston 14.

The casing 12 consists of a lower section 18 which functions as asampler tube and which is formed with a sharp cutting edge 20, and anupper section 22 which is provided with a portion 24 of enlargedinternal diameter. The diameter of the cutting edge 20 is such that itforms a snug fit around the head portion of piston 14 and is preferablyformed by first spinning the edge of the casing in and thereaftermachining it to a cutting edge 20 with an inside diameter smaller thanthe rest of the casing. If desired, however, the integrally formedcutting edge may be replaced by a detachable shoe of, for example,hardened steel, coupled to the lower section 18 of casing 12 in anysuitable manner. The upper end of section 18 and the lower end ofsection 22 are provided with shoulders whereby the two sections may beflush-jointed with each other to provide a streamlined exterior surface.The upper section 22 is preferably formed as a single unit but may, ifdesired, be formed from a number of interconnected sections.

The piston head is of generally conical form and the piston neck isprovided with an 0 ring 28 which, upon the complete retraction of thepiston, ensures a perfect seal between the piston and the casing. Theneck of piston 14 is of smaller diameter than the bore of casing 12 andis provided with an arcuate longitudinal extension 39 which in theembodiment shown extends around the neck through a sector. The rod 16 ispreferably formed as an integral unit machined from one piece ofmaterial, although it may, if desired, be formed from a number ofinterconnected sections. The rod 16 is provided at one end with anexternally-threaded portion 34 adapted to be threaded into theinternallythreaded portion 36 of the piston base. The rod 16 is alsoprovided with a number of spaced-apart arcuate lugs 32 each of which inthe embodiment shown extends around the rod through a section.Preferably, the lugs 32 are machined out of the material forming therod, although they may, if desired, be formed as separate units whichare securely attached to the rod either permanently or detachably in anysuitable manner. The interior of the casing is provided with a likenumber of arcuate segments 40 extending around the casing through, forexample a 150 section, the lower edge of the lower most segment forminga bumper adapted to abut the arcuate extension 34 of piston 14 uponretraction of the piston from its driving to its partially retractedposition. A key 42 is formed on the outer surface of rod 16 above theuppermost of said segments and the key co-operates with a keyway 44formed in a ring 46 to prevent rotation of the rod 16. The ring 46 issecured to the inner surface of the casing 12 in any suitable manner andto facilitate assembly it is preferably formed in two halves.

A plurality of arcuate stop members 48 are located within casing 12,each stop member 48 extending through, for example, a 45 sector therebyleaving a 7 /2 play on each side of the lugs 32 and each aligned withthe space between two adjacent ones to segments 40. The stop members 48may be formed integrally with the casing 12 although they are eachpreferably formed as a separate piece securely attached to the casing 12by means of screws 50.

The top of the uppermost section 22 of casing 12 is enlarged to form asleeve into which the enlarged section of rod 16 snugly fits. The sleeveand the enlarged section co-operate to increase the resistance of thesampler to bending. Below the enlarged section any bending movement istaken jointly by the rod and the casing. An ring 54 is provided in theenlarged section of rod 16 and this 0 ring effectively seals the sampleragainst the ingress of air or other matter during advance ment of thesampler into the soil. Above the enlarged section, the rod is providedwith a head 56 having shoulders 58 adapted to engage the upper edgeofcasing 12 when the sampler is being driven into the ground. The head 56is provided with an internally-threaded recess 59 into which extensionpieces 69 for rod 16 may be fitted.

With the sampler assembled and the piston 14 in its lowermost position,whereat it seals olf the lower end of the casing, the sampler isadvanced into the ground in any suitable manner. During the advancementof the sampler into the soil, the piston effectively seals off the lowerend of the casing, thereby preventing any soil entering the samplerduring advancement thereof. It is also to be noted that duringadvancement when the resistance to the driving force is greatest, thedriving force is transmitted directly to both the piston and the casingfrom the rod. The casing transfers the driving force to the sample tube,whilst the lugs and segments do not transfer any force during thisoperation.

When the desired sampling depth has been reached, rod 16 and piston 14are retracted to a position whereat the arcuate extension 30 of thepiston abuts the lower edge of the lowermost one of segments 40. Thecasing is prevented from retraction at this time by the friction betweenthe outer wall thereof and the surrounding soil. Furthermore, duringthis initial retraction of the piston, as soon as the piston iswithdrawn from the cutting edge 20, air can pass into the section 18 ofthe casing therebelow through the small clearance between the piston andthe casing and consequently creation of a vacuum below the piston isprevented at this stage. The key 42 and associated keyway 44 co-operatesto prevent rotation of the rod relative to the casing during thisinitial retraction. With the piston in its partially retracted positionthe key is clear of the keyway and the lugs 32 are situated opposite therecesses 62 between adjacent ones of the segments 44). The rod 16 andpiston 14 are now rotated in a clockwise direction through an anglesufiicient to bring each lug 32 into a corresponding one of saidrecesses 62 above one of the segments 40. R0- tation of the lugs 32 pastthe segments 40 is prevented by the stopper members 48.

The sampler is now ready for the actual sampling operation with thepiston 14 adjacent the upper end of the lowermost section of the casingwhich is now, as a result, open at its lower end. The sampling is noweffected by exerting a downwardly directed vertical force on theenlarged head of rod 16, which force is transmitted from the rod to thecasing through the intermediary of the lugs 32 and segments 49 toadvance the casing a distance corresponding to the length of the openportion of the casing, thereby to force a soil sample into the lower endof the casing. During sampling, the air below the piston can escapeupwardly through the clearance space between the piston and the casing.The casing itself may be vented either internally by means of a boreextending longitudinally through the rod and communicating with apassage opening into an outlet at or in the piston or externally throughan opening formed in the ring 46.

After the sample has been taken, the sampler is now ready for withdrawalout of the ground. To effect withdrawal of the sampler, an upward forceis exerted on the rod and piston to pull them to the fully retractedposition of the piston, whereas each of the lugs abuts against theuppermost edge of its associated recess and the leading edge of the neckof the piston moves into the casing. In moving the piston from thepartially retracted to fully retracted position two actions take place.During the initial part of this movement of the rod and piston relativeto the casing, the piston rid becomes effective to seal the lower end ofthe casing against ingress of air. During the final part of themovement, the piston ring by its travel creates a partial vacuum abovethe sample. This partial vacuum helps to prevent loss of the sampleduring the withdrawal operation. With the piston in its fully retractedposition, further upward movement of the rod serves to withdraw thesampler and its enclosed sample to ground surface level.

What I claim as my invention is:

1. Soil sampling equipment comprising in combination a tubular housing,a sample tube detachably connected at its upper end to the housing andformed at its lower end with a cutting edge, a piston slidably mountedwithin said sample tube and adapted to seal off the lower end thereof, apiston rod connected to the upper end of the piston and extendingupwardly through the sample tube and the housing, said piston rod beingformed at its upper end with an enlarged head portion adapted with thepiston in its fully extended position to engage the upper edge of thehousing whereby downward pressure applied to the upper end of the rod istransmitted to both the housing and the piston, a plurality of arcuatelugs on the rod spaced-apart longitudinally thereof, a plurality ofarcuate segments formed on the inner surface of the housing andspaced-apart longitudinally thereof, said lugs and said segments adaptedto cooperate releasably to lock the rod and the housing in downwardlydrivable engagement upon partial retraction of the piston through thesample tube and in upwardly drivable engagement upon further retractionof the piston to its fully retracted position, a plurality of stopmembers on the inner surface of the housing intermediate said arcuatesegments, said step members cooperating with the arcuate lugs to limitthe rotational movement of the rod relative to the housing thereby tofacilitate alignment of the lugs and the segments for intercoupling saidrod and said housing, vent means between the piston and the innersurface of the sample tube effective with the piston in its partiallyretracted position to vent the section of the sample tube below thepiston, and means associated with the piston and adapted upon movementof the piston upwardly from its partially retracted position to seal offthe vent means whereby during the further retraction of the piston toits fully retracted position a vacuum is created above a soil sampleforced into the sample tube upon downward movement of the housing aftersaid initial partial retraction of the piston.

2. Soil sampling equipment comprising in combination a tubular housing,a sample tube detachably connected at its upper end to the housing andformed at its lower end with an annular cutting edge, a piston slidablymounted within the sample tube and adapted to seal off the lower endthereof, a piston rod connected to the upper end of the piston andextending upwardly through the sam ple tube and the housing, said pistonrod being formed at its upper end with an enlarged head portion adaptedwith the piston in its fully extended position vto engage the upper edgeof the housing whereby'downward pressure applied to the upper end of therod is transmitted to both the housing and the piston, a plurality ofarcuate lugs on the rod and spaced-apart longitudinally thereof, aplurality of arcuate segments formed on the inner surface of the housingand spaced-apart longitudinally thereof, said lugs and said segmentsadapted upon withdrawal of the piston a predetermined distance towardsthe upper end of the sample tube and rotation of the rod relative to thehousing to interconnect the rod and the housing whereby subsequentdownward pressure exerted on the upper end of said rod is transmittedthrough the lugs and segments to the housing to urge the latterdownwardly thereby to force a soil sample into the sample tube, saidlugs and said segments effective upon further withdrawal of the pistonthrough the sample tube after collection of the soil sample to couplethe rod and the housing in up wardly drivable relationship wherebysubsequent retraction of the rod is effective to retract the housing andthe sample tube, a plurality of stop members on the inner surface of thehousing intermediate said arcuate segments, said stop memberscooperating with the arcuate lugs to limit the rotational movement ofthe rod relative to the housing thereby to facilitate alignment of thelugs and the segments for intercoupling said rod and said housing, ventmeans between the piston and the inner surface of the sample tubeeffective with the piston in its partially retracted position to ventthe section of the sample tube below the piston, and means associatedwith the piston and adapted upon movement of the piston upwardly fromits partially retracted position to seal off the vent means wherebyduring the further retraction of the piston to its fully retractedposition a vacuum is created above the soil sample.

3. Soil sampling equipment comprising in combination a tubular housing,a sample tube detachably connected at its upper end to said housing,said sample tube formed at its lower end with a portion of reducedinternal diameter terminating in a cutting edge, a piston slidablymounted within the sample tube and adapted in its fully extendedposition to form a snug fit in said portion of reduced diameter therebyto seal off the lower end of the sample tube, a piston rod connected tothe upper end of the piston and extending upwardly through the sampletube and the housing, said piston rod being formed at its upper end withan enlarged head portion adapted with the piston in its fully extendedposition to engage the upper edge of the housing whereby downwardpressure applied to the upper end of the rod is transmitted to both thehousing and the piston, a plurality of arcuate lugs on the rodspaced-apart longitudinally thereof, a plurality of arcuate segmentsformed on the inner surface of the housing and spaced-apartlongitudinally thereof, said lugs and said segments operable releasablyto interconnect the rod and the casing in downwardly drivable engagementupon partial retraction of the piston through the sample tube and inupwardly drivable engagement upon further retraction of the piston toits fully retracted position, a plurality of arcuate stop members on theinner surface of the housing intermediate the arcuate segments, saidstop members cooperating with the arcuate lugs to limit the rotationalmovement of the rods relative to the hous ing thereby to facilitatealignment of the lugs and the segments for intercoupling the rod and thehousing, an annular vent passage between the piston and the innersurface of the sample tube above said portion of reduced iametereffective to vent said sample tube to the housing, and means associatedwith the piston and adapted upon movement of the piston upwardly fromits partially retracted position to seal olf said vent passage wherebyduring the further retraction of the piston to its fully retractedposition a vacuum is created above a soil sample forced into the sampletube during the downward movement of the housing after said initialpartial retraction of the piston.

4. Soil sampling equipment comprising in combination a tubular housingmade up of a plurality of interfitting sections, a sample tubedetachably connected at its upper end to said housing, said sample tubeformed at its lower end with a portion of reduced internal diameterterminating in a cutting edge, a piston slidably mounted within thesample tube and adapted in its fully extended position to form a snugfit in the portion of reduced diameter thereby to seal off the lower endof the sample tube, a piston rod connected to the upper end of saidpiston and extending upwardly through the sample tube and the housing,said piston rod being formed at its upper end with an enlarged headportion adapted with the piston in its fully extended position to engagethe upper edge of the housing whereby downward pressure applied to theupper end of the rod is transmitted to both the housing and the piston,a plurality of arcuate lugs on the rod spaced-apart longitudinallythereof, a plurality of arcuate segments formed on the inner surface ofthe housing and spaced-apart longitudinally thereof, said lugs and saidsegments adapted to cooperate releasably to lock the rod and the housingin downwardly drivable engagement upon partial retraction of the pistonthrough the sample tube and in upwardly drivable engagement upon furtherretraction of the piston to its fully retracted position, a plurality ofstop members on the inner surface of the housing intermediate saidarcuate segments, vent means between the piston and the inner surface ofthe sample tube above said portion of reduced diameter effective to ventsaid sample tube to the housing, and means associated with the pistonand adapted upon movement of the piston upwardly from its partiallyretracted position to seal off said vent means whereby during thefurther retraction of the piston to its fully retracted position avacuum is created above a soil sample forced into the sample tube upondownward movement of the casing after said initial partial retraction ofthe piston.

5. Soil sampling equipment comprising in combination a tubular housing,a sample tube detachably connected at one end to the housing andprovided at its other end with a cutting edge, a piston slidably mountedwithin the sample tube and adapted to seal off the lower end of the rsample tube, a piston rod connected to the upper end of the piston andextending upwardly through the sample tube and the housing, said pistonrod being formed at its upper end with an enlarged head portion adaptedwith the piston in its fully extended position to engage the upper edgeof the housing whereby downward pressure applied to the upper end of therod is transmitted to both the housing and the piston, a plurality ofcomplementary formations on the outer surface of the rod and the innersurface of the housing, said formations spaced-apart longitudinally ofthe rod and the housing and effective upon partial retraction of thepiston through the sample tube and rotation of the rod relative to thehousing to couple the rod and the housing in downwardly drivableengagement and in upwardly drivable engagement upon further retractionof the piston to its fully retracted position, a plurality of stopmembers on the inner surface of the housing intermediate the formationsthereon, said stop members cooperating with the formations to limit therotational movement of the rod relative to the housing thereby tofaciliate alignment of the complementary formations for intercouplingthe rod and the housing, means between the piston and the inner surfaceof the sample tube effective with the piston in its partially retractedposition to vent the portion of said sample tube below said piston, andmeans associated with the piston and adapted upon movement of the latterfrom its partially retracted position to seal off the vent means wherebyduring the further retraction of the piston to its fully retractedposition a vacuum is created above a soil sample forced into the sampletube upon downward movement thereof after said initial partialretraction of the piston.

6. Soil sampling equipment comprising in combination a tubular housing,a sample tube detachably connected at one end to the housing andprovided at its other end with a cutting edge, a piston slidably mountedwithin the sample tube and adapted to seal off the lower end of thesample tube, a piston rod connected to the upper end of the piston andextending upwardly through the sample tube and the housing, said pistonrod being formed at its upper end with an enlarged head portion adaptedwith the piston in its fully extended position to engage the upper edgeof the housing whereby downward pressure applied to the upper end of therod is transmitted to both the housing and the piston, a plurality ofarcuate lugs on the housing spaced-apart longitudinally thereof, aplurality of arcuate segments formed on the inner surface of the housingspaced-apart longitudinally thereof, said lugs and said segments adaptedupon partial retraction of the piston towards the upper end of thesample tube to interconnect the rod and the housing whereby subsequentdownward pressure exerted on the upper end of the rod is transmittedthrough the lugs and the segments to the housing to urge the latterdownwardly thereby to force a soil sample into the sample tube, saidlugs and said segments effective upon further retraction of the pistonto its fully retracted position after collection of the sample to couplethe rod and the housing in upwardly drivable engagement, a passagebetween the piston and the inner surface of the sample tube efiectivewith the piston in its partially retracted position to vent the sectionof the sample tube below the piston and adapted to be sealed uponmovement of the piston from its partially retracted position wherebyduring the further retraction of the piston to its fully retractedposition a vacuum is created above a soil sample forced into the sampletube upon downward movement thereof after said initial partialretraction of the piston.

References Cited in the file of this patent UNITED STATES PATENTS

